Sir Alex Ferguson admits Wayne Rooney is a doubt for Saturday's massive Premier League showdown with Chelsea after limping off during Tuesday night's Champions League defeat by Bayern Munich.
The Manchester United frontman hobbled off towards the end of the Red Devils' 2-1 defeat in the first leg of their quarter-final.
The England ace, who had been on target in the game at the Allianz Arena, went over on his right ankle in the dying seconds of the first leg clash.
He looked to be in some pain as he left the field, with fears immediately raised as to his continued involvement for United this season and at this summer's World Cup.
It is too early to say how badly the in-form striker has been hurt, but Ferguson accepts that he may be unavailable for a mammoth top of the table clash with Chelsea at Old Trafford this weekend.
"He has got a kick to the ankle, we will just have to wait and see tomorrow (Wednesday)," Ferguson told Sky Sports.
"Hopefully it's not too serious. He may be doubtful for Saturday but we don't know, it's too early to say."
Rooney could also be a doubt for the return date with Bayern next Wednesday, as United look to overturn their first-leg deficit.
They edged ahead early on in Munich, but saw Franck Ribery Ivica Olic and peg them back.
Ferguson admitted afterwards that United were a long way from their best, but believes their away goal could prove crucial in a tie which is far from over.
"We didn't play well enough to be honest, we kept giving the ball away. We caused our own defeat," he said.
"Bayern were the better team, we can't complain about that, but we're better than that in possession. We kept giving it away and that was our downfall.
"The first goal was a bit of luck with a deflection but the last goal, I don't know how you describe it. The game was done and we gave a terrible goal away."
He added: "Old Trafford will be a different game obviously.
"We will be much better, no doubt about that, and hopefully we can recover.
"We have the away goal and we'll go out to win the game."
